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J Burns

On 8/27/14, 3:09 PM, wrote:
On Wed, 27 Aug 2014 14:19:08 -0400, Jan Philips
wrote:

It was working again until today. The thermostat is a basic Aprilaire
model.

I left it set on 74 and it was 77 when I got there - same as before,
but not so hot, so it must have been working until a few hours ago.

I went through the procedure that worked the other two times. This
time it did not work. The 'stat has an indicator that indicates that
it is calling for cooling. It was flashing "cooling" when I turned it
back on. Then after the minute or two delay, I heard the click that
is made when the compressor starts. But the compressor did not start.

We are renting out this house starting sometime in September, so I
need to make sure it is fixed, so I called my usual repairman.

Thanks for all of the helpful replies and ideas.

Be aware there may be a time delay relay in the compressor control box
that prevents it from starting within 3-5 minutes after the call for
cooling on a restart.

Switching the thermostat off could account for the two-minute delay
while the display flashed. The subsequent click shows that the
compressor was getting the "start" signal.

My guess that it was a bad contactor was ignorant. It's usually the
capacitor. They can lose capacitance over the years. If the compressor
starts sometimes but not others, the capacitance is probably marginal.

Replacing a capacitor seems like a DIY job. Buy the right size and
switch off the breaker.